1. Field of the Invention
This invention relates generally to exact cup measuring tea kettles, and particularly to such a tea kettle which is capable of measuring the amount of water or other fluid within the kettle as the kettle is being filled with the fluid.
2. Description of the Prior Art
It is known generally to provide tea kettles, and the like, with devices for measuring the amount of liquid within the kettle. Several examples of which known devices were cited in my application Ser. No. 767,944, filed Feb. 11, 1977. In addition, Dutch Pat. No. 86,284, issued Sept. 16, 1957, to A. W. Wolven, discloses a fluid kettle having a spring attached to a pivoted handle and affixed to the stationary portion of the kettle for providing a determination of the amount of liquid within the kettle. A suitable lock is provided for securing the handle against swinging movement as desired when manipulating the kettle for pouring liquid from same, and the like. A basic disadvantage against using a simple coiled spring in the manner shown in this Dutch patent is that the kettle can only register the mass contained therein after the charge is received and the kettle is placed in a control position to level and calm the sloshing liquid. Reversed tangential forces caused by sloshing water, plus recoiling stress on the spring, will increase in intensity, setting up a varying plus and minus reading on the device. Thus, the arrangement as shown in the Dutch patent is not suitable for use in reading the amount of water in the kettle as the kettle is being filled in order to avoid placing an excess amount of water than that amount needed into the kettle.
U.S. Pat. Nos. 733,411, issued July 14, 1903, to W. Maxwell, and 791,554, issued June 6, 1905, to H. Hathaway, disclose weighing devices which employ a coil spring as a resistance against which the weight of an object is measured. It is apparent, however, that these known weighing devices cannot be readily installed onto a tea kettle for measuring the quantity of fluid in same, inasmuch as the resultant structure would have the same disadvantages as the kettle disclosed in the Dutch patent discussed above.